Telephone-exchange system.



H..rJ.sTm1uD.v TELEPHONE EXCHANGE SYSTEM. AEPMCATION FILED SEPT. 2. 1902. RENEWED AUG. I, 1905.

` ,229,165.l PatentdJune 5,1917;

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ing subscribers iteni .wherein each subscriber-s line STATES PATENT oEEIcE.

ILLINOIS, ASSIGNOR, :BY MESNE ASSIGNMENTS, TO

CORPORATION OF ILLINDIS.

TELEPHONE-EXCHANGE SYSIIEIIHI.y

Specification of Letters Patent.

Patented June 5, 1917.

Application le. September 2, 1902, Serial No. 1721,79?. Renewed August 7, 1905. Serial No. 273,197.

To all whom it may concern.'

vBe it known that I, HAROLD l).4 STROUD,

i citizen' ofV the4 United States, residing at Chicago, Ain the county of Cook and State of Illinois, have invented' a certain new and useful Improvement in TelephoneExchan e Systems, of which the followingis a fu l, clear, concise, and exact description, reference being had to the accompanying drawings, forming a parto this speci'iication.

My invention relates to telephone eX- change'systems, and has for its object the provisiono automatic means for connecttelephone lines with cord circuits, which cord circuits are also provided with manually operated means for uniting the same with telephone lines for completing connection between subscribers.

By means of my invention, to have the calling subscribers line automaticallyconnected with the answering end 4,of the cord circuit, the connecting end of K the cord circuit being preferably provided 25 with a connecting plug adapted for insertion within any of the line jacks.

In another aV lication, Serial No. 69,681, tiled July 25', lillll, I have disclosed a sys- 1s equipped with a traveling springjack adapt ed to be operated through the agency of apparatus actuated when a call is initiated, which spring jacir, in its movement, is brought into nner-.tion with the terminals of an idle co circuit or connector, at the answering end thereof; tromagnetic device has its operative condition changed to cheri; the further movement of the traveiing spring jack to maintain the same in engagement with the said cord clrcuit termlnals, whereby the cord clrcuit Y constitutes a continuation of the calling sub- 'scribers line, 'the spring jack being provided with springs connected with the sides of the said telephone line.

In my present invention, instead of yequipping the subscribers line with the traveling spring jacks, .I equip one end of each cord circuit, the answering cud, with what may be termed a traveling plug, or its electrical equivalent. In this I am enabled to greatly reduce the motor mechanisms required for effecting the traveling of the movable connecting devices, and consequently am able to greatly simplify the constructnm: The 1n vention disclosed 1n my said 'capendmg aptravel of the answering contacts. traveling contacts are caused to pass over av I am enabled gaged fror operative relation whereupon an elec-A general characteristics', but somewhat specic in some of its aspects.

In my present invention I employ, at the answering end of each cord circuit, a contact or contacts corresponding to the cord circuit, which contactsV may be termed ans wering contacts, meaning thereby that they constitute the terminals of the answering end of the cord circuit, motor mechanism being associated with these answering contacts preferably constantly electing the These plurality of line contacts that register therewith. The motor mechanism for op erating the answering contacts is preferably controlled in "its operation by an electromagnet or relay, which electro-magnet or relay in turn is adapted for control from a calling sub-station, the arrangement being such that when a^traveling answering contact engages a contact of an unselected calling line, the relay is placed in a condition. of energization, owing tothe removal of the telephone receiverfrom theswitch hook :rt the calling substation, to cause the motor mechanism of the cord circuit' to be di' nwith thc cof'-Y responding answering contacts, so that a calling subscribers line, when thus automatically connected with the answering contacts, is maintained in such connection.

Each answering end of a cord circuit may be associated with fifty sets of line contacts, for example, while the line contacts that are for association with moving answering contacts may be multipled as many times as there are cord circuits to be connected there with at va 'given section of board or operators position.

The system that I have thus briefly outm lined isone that is well adapted for multipliswitchboard work or trunking systems. There is preferably associated with the relay that is governed by the calling subscriber for controlling the motor mechanism that. actuatee the answering contacts, a signal. there being thus preferably no relayimcha nism and no signaling apparatus perinanently associated with an idle line. there being only as many relays as there are cord circuits. A signal may thus serve in a double capacity of a line signal and a clearscriber.

ingout signal. When a call is initiated the signal acts as a line indicator, the plug at the connecting end of the cord circuit being in its seat correspondin inposition to the indicator, which is pre erably a small 1ncandescent lamp. When conversation has been finished, or when a subscriber (now preferably the called subscriber) has restored his telephone, the lamp, again glowing, enables the operator to determine that the called subscriber has restored his telephone, as the plug no longer occupies a position corresponding to the signal, being in serted within the ]ack of the called subscriber. When conversation is finished, the replacing of the receiver at the calling telephone will release the traveling plug which will then continue in its travel. Should there then be another unselected calling subscriber in the same group, said traveling plug, or some other, will select the said sub- In case said calling subscriber be selected by said released traveling plug prior to the disconnection of its corresponding cord-circuit, the called' subscriber having also hung up, the new call will be indicated by the signal vupon the operator withdrawingkthe plug from its previously connected gac Where double supervision is desirable, a special signal is addedto the cord circuit, which preferably only gives a"disconnect signal, which signal is under the control of the callinosubscriber. There may be associated wit-l1 the cord circuit an electro-mag netically controlled listening key, in associa'- tion with a plug seat switch, or equivalent means, whereby, when a call is initiated, the voperator will have her telephone partially connected with the calling subscribers line, which connection of the operators line with the cord circuit may be completed upon the removal of the connecting plug from its seat.

In this way a number of calls may be received before any of them are responded to; while at the same time all the operations in establishing a connection may be performed in orderly sequence.

The ringing key, in association with these cord circuits, is preferably manually controlled owing to commercial conditions that now so largely obtain. A system of my invention will enable the operators to effect connections between telephone lines with very few movements to each given connection, eil'ecting corresponding increase in the operators capacity. As there is only one manuall controlled plug, two -plu movements or each connection are dispensed with. As there may be no manually operatedlistening, key used in effecting a connection, another motion is dispensed with for eajclp connection.

In modern practice, line indicators, even though very small in the aggregate occupy nasales a great deal of space upon the switchboard, which, particularly where multiple switchboards are concerned, introduces a factor that is expensive in point of switchboard construction and capacity. By means of my invention, an indicator, associated with each cord circuit only, may act as the line indicator, and especially when acting as a supervisory indicator it may be located upon the switchboard shelf, the vertical portion of the switchboard being thus relieved of any apparatus except the jacks, enabling the space that has hitherto been occupied by line indicators to be occupied by multiple jacks, thus largely increasing multiple switchboard capacity. Further, the answering contacts of a` multiple switchboard line, be` ing associated with the movable answering contacts, are not located upon the vertical face of the switchboard, but together with the said answering contacts and the motor mechanism controllingthe same may be located elsewhere in the exchange building.

I will explain my invention more fully by the drawing, in which Figure l illustrates the applicationof my invention to a telephone exchange system, and Fig. 2 somewhat diagrammatically indicates the motor mechanism` and the relay mechanism for controlling the same. Like parts are indicated by similar characters of reference throughout both figures. At each'of the substations, and 120, is shown a telephone switch hook l, a-telephone receiver 2, adapted to be supported thereby, a signal bell 3, that may be of any well known type, as,for example, a polarized ringer, a condenser 4, in the 'same bridge with the bell, to prevent the flow of common battery, where employed, over the telephone lines, a transmitter 5, an induction coil 6, the primary of which is included in circuit with the telephone lines in a common battery system, while a secondary may bev included in a closed local circuit with the receiver.

For Apurposes to be hereinafter set forth, the primary winding' of the induction coil also preferably constitutes an energizing 'winding of an electromagnet for effecting the attraction of an armature 7, which, when released, serves to throw the ground connection 8 on one side of the telephone line 9. This side of the telephone line, however, has no instrumentality at the exchange corresponding to such ground connection. The companion side 10 of each telephonel line is periodically grounded at the exchange, in a manner to be hereinafter fully set forth, through a relay 11 and battery 12. There is, however, interposed between each relay 11 and the ground 8 for connection with limb 10, a substation switch hook l, which when depressed removes the ground 8 from the relay 11, but which, when elevated, throws this ground 8 on to the relay, thereby com- 130 letingcircuit 'through said relay. This reay circuit includes a common battery 12 that may also be employed for supplying transmitters 5 with battery current, the of- 5 tice ground foi-.the relay 11,'being indi cated at 13. The relay 11 is preferably included in one strand, or the continuation of one strand 14, and has for its special and ,prime function the control, of the motor mechanism 15, 'employed for effecting. the travel of the answering contacts 16, 1T. This control of the motor mechanism may be effected in a variety of ways. 'I have shown an electro-magnet 18, 1for the purpose of cooperating in this control, which elcctromagnet is normally energized through the agency of the armature of magnet 11, and the normal contact engaged by this arma ture when the magnet 11 is d energized.

yit being always energized so long as an unn selected calling line isfnot in connection with an answering Contact 16, effects the bodily movement of a plate 19 away from the traveling answering contact 17, vpermitting the plate 20 to remain in engagement with the traveling answering contact 16, but one of these vplates being moved. For this purpose the plate 19 may be splined upon the nondriven shaft 21. There is interposed between the magnet 18 and the plate 19 a coiled spring 23 =to quickly thrust the plate 19 against the traveling contact 17, when the magnet 18 is denergized to duly provide the maintainin circuit for 'relay l1 as hereafter' specified. "he plates 19 and 20 are provided with the line terminals 24 and 25 preferably circularly arranged, and around which the contacts 16, 17 are rotated by the motor 'l5 through the agency of gearing 22. Each pair of radially alined contacts 2&1` and 25 constitutes the connecting contacts of a calling subscribers line.

There are several lines, fifty or more if desirable, thus represented by their connected contacts in association. with a pair of traveling answering cord contacts. The answering end of each cord circuit is equipped withsuch a pair of answering contacts 16 and 17, and in order that any calln ing line may be automatically connected with/answering cord contacts, each tele phone line has as many pairs or sets of con necting contacts as there are cords to be connected rtherewith at an operatorie posi tion,",or a section of switchboard. I have illustrated in Fig. 1 the connecting contacts 24 'and 255 multipled for the cbrd circuits, "but obviously `the number of cord circuits andthe number of pairs of connecting contacts fof'flines will be increased in actual a l'iracticeif Whenl a 'subscriber initiates a call,

1heremov'e's .his telephone from the hook lever and". closes th common battery 1 2 `into circuit withthe relayyll, theyclrcuit Magnet 18 by being thus normally energized,-

through this relay being traced from the ground 13, the battery 12, a winding 26 of a repeating coil (repeating coils limiting the `subscribers transmitter current to a tenth of an ampere being desirably employed in the cord circuits) the helix of themagnet 11, answering contact 16 (which has been brought by the previous constant operation of the motor mechanism into connection with the contact 25 of the calling subscriber 120, for example), a line contact 25, limb of the telephone line 10, telephone switch hook 1, primary winding of induction coil 6 and the ground 8, at the substation, now thrown on to the limb 10, by the elevation of the switch hook. When circuit has been thus established through the magn net 11, a further continued movement oi the answering contacts 16 and 17 is prevented, when the m'otor 15 is an electric motor, by the movement of the armature toward the magnet 11, therebyv opening the circuit that previously included the battery 12 and the motor 15, the pressure of the spring contacts 16 and 17 being sullicient to bring the motor to rest directly after it. is placed on open circuit. The magnet 11 may further be caused to operate a signal 27 preferably in the formV of a small forty volt incandescent v lamp, this signal being operated when the armature of the magnet isattracted, the signal then being operated as a line indicator to show the operator that subscriber 120 desiresconnection. The'circuit through this indicator may be traced from the battery 12 to the armature of magnet `11, the contact engaged by the armature upon its attraction, the contact and armature of magnet 28, the lamp, returning to the battery.

The operator havin received a call, may operate her listening ey 29, .when the cord circuit, shown upon the rightof the drawing, is employed to include her telephone in circuit with the calling subscribers telephone, the resistance of the operators cir cuit being such that it will not unduly shunt the subscribers line.l Having ascertained the connection desired, the operator removes the connecting plug 50 from its seat (this connecting plug comprising the connecting terminals of the cord circuit in telephonie connection with theanswering contacts se lectedly connected with the calling subscribers line) and thereafter inserts this plug within the line iack of the called sub scribers telephone line, wherea'fter the operator depresses the ringing key 31 to include the calling generator 32 in circuit with the called subscribers signal bell.

There is included in circuit with thelamp 27 a plug 'seat switch 38 which serves to maintain the circuit including 'thisV lamp open when the plug is normal. This 1s provided because the armature ci the magnet 428 "would, otherwise constantly maintain the 'lic ignaling current through the lamp, the.

armature closing circuit when unattracted.

.The cord-connecting apparatus illustrated circuit containing the intermediate contact 41 of the connecting plug 42, and, when said plug is inserted Within a jack of a called subscriber, a Agrounded iaclt spring 43, the spring 43 thus constituting onegrounded terminal of the agnet /iOWhile the other terminal of the .magnet 40 is grounded through battery l2 at 13. rl`he armature of this electromagnet, when unattracted, serves to close a break in the operators telephone circuit, so that when a call is initiated the operator may listen. vWhen the connecting plug that has been automatically connected with a calling subscriber has been inserted Within the called subscribers jack, the inagnet 40 is energized, withdrawing its armature so as to open the circuit including the operators telephone utt.

In order that a number of incoming signals may be received and to prevent con fusion in the Work of the operator, the telephone circuit at the left preferably also includes a plug seat switch 44, which While the plug is in its seat serves to maintain a second opening in the operators circuit, this opening being closed when the plug is removed. lt it should be desired to have the operator listen in at any time after connection is established, there is included in circuit with the magnet 4G a listening key 45, which, when depressed, Will open the circuit containing the magnet 40, throwing the operators telephone set into circuit by reason of the release' of the armature of such mag-- lIn'itter is included in circuit with the conimon battery the armature controlled by the primary Winding. at the substatipn of the' calling subscriber is attracted to remove the groundI 8 frogin theline. i Thiscondition only Aarrseswhen an automatic selection has been ground at the substation.

Lesesaal effected and the battery is flowing over the metallic circuit of the line.

previously stated, the relay ll is initially energized over a circuit extending to lt will also be observed that as soon as this ground is removed by the attraction of the armature '7, a maintaining circuit for the 4relay 1l is continued through the transmitter` 5, line lirnb 9, contacts 1'7-24 (which are engaged upon the denergizationy of magnet 18), the Winding of relay 4T and a Winding of repeating coil 26 to ground. New, il? a second. switch, in Search of a calling line, temporarily connects its trunk With contact of an already selected line, the stopping relay ll and a winding of the repeating coil 26 of the second trunk Willbe placed in shunt With the stopping relay 1l and the correparallel pat'lisinclude-,Sonfthe one hand, re-

sponding Winding of the repeating coil 26 of the first trunk, thereby connecting the resistances of the line liinb l0, coil 6, together With the vresistance of theY substation transmitter 5, line limb 9, relay 4'( and a Winding of repeating coil 26, in series .with gg the'said parallel paths through the relays l1. By reason of the inclusion of this additional resistance in circuit, the current lowing through the'tWo relays 11 will be so far re-Y duced as not to actuate 'the relay 11' of the second trunk and yet not to permit the release of relay 1l of the lirst trunk. It will also be'observed that the temporary connection or' a second trunk to contact 25 of a called line, similar tothat runing to substation 90, results in forming a similar cir-v cuit having parallel and series portions. In. this case, one parallel path includes a Winding of repeating coil 26 and relay l1, and the other includes relay 28.' The series portion oi' the circuit includes line limb l0, Winding of induction coil 6, transmitter 5, line linib 9, and a Winding of repeating coil 26. With these resistanccs, as before, the relay 1l of a second trunk Will not be actuated and relay 22S-Will not release its armature. It will also be observed that the ternporary connection of a second trunk to contact25 of a called line, similar to that running to substation 120, also results in forminga circuit having parallel and series portions. n this case the parallel paths include on the one hand relay 11 and a Winding of repeating coil 26, and on the other hand a Winding of repeating coil 26 only. As be- 120 fore, the resistances are lsuch that the relay ll of the seeking trunk is not actuated. It Will also be observed that the temporary connectio'n of a second trunk to contact 25ct a called line, similar to thatrunning to sub 125 station. 120, assuming that the operator at that time has her listening key 29 depressed. also results `in forming a circuit having parallel and 44:reries portions. "In this case the line and .a called line, a plurality of link.

nected to traveling contact Amakers' capable of assuming a plurality of selective positions for connecting With` said. answering contacts.

9. A telephone system including a calling circuits at the exchange for use in interconnecting said lines, manually operated tervininals for certain of said circuits for connecting with said called line, multiply related vpassi-vev contacts of said calling line at the exchange, contact members for certain oie said linka-circuits adapted to be moved to engage saidcontacts, and apparatus at the calling station effective under control of the subscriber to control said contact members to automatically temporarily connect a link- I circuit With the line.,

l0. A telephone system including a calling and a called line, a plurality of link-circuits at the exchange each adapted to interconnect said lines, manually operated terminals for said circuits for connecting -With said called line, multiply related non-traveling contacts of said callin@ line at the exchange traveling contact members for said link-circuits adapted to engage said non-traveling contacts, and apparatus at the calling station eilective under control of the subscriber to control said contact. vmembers to automatically temporarily connect a link-circuit with;

' f the line.

il. l telephone system including acca-lling line and a called line, a plurality ci link-- circuits at the exchange for use in interconnecting said lines, operator controlled terminals for certain of said circuits for connecting with said called line, multiply related passive contacts of said calling line at the exchange.3 contact members for certain of said link-circuits adapted to be moved to,

engage 'said contacts, apparatus at the calling station effective under control ot the subscriber to cont-rol said contact member to automatically temporarily connect a linkcircut with the line, and mechanism automatically effective to extend a calling signal.

l2. A telephone system including lsubscribers lines each having multiple answering contacts and multiple called contacts, link circuits l'or use in connecting subscribers lines for conversation, each of certain of said link circuits being connected to a manually operated terminal. foruse in eXl tending connections tov said called contacts and 'certain of said link circuits being'connected to traveling Contact inalers capable ,of assuming aplurality of selective positions `:tor connecting Wit said answeringcontacts,

and means at a substation for automatically* bringing the traveling contact makers of link circuit into ateinoorar continuin con-A nection with tne stationary contactsv of the line. A

13. A telephone system including a calling line, passive line contacts thereforQat the eX- cliange, operator controlled link-circuits for use in extending connections from calling to called subscribers and manually controlled terminals for certain of said link circuits,

certain of said link circuits having selective lective switches proyided with traveling contact members adapted to engage said nonvtraveling contacts, and means at the substation :tor automaticallyT causing. a continuing connectionl of one of said link-circuits With said line contacts.-

15. A teleplionesystem including a callingline, passive line contacts'thereior at the eircha'nge, operator controlled link-circuits for use in extending connection from calling to called 4subscribers 'having selective switches provided With Contact members adapted to bamoved to engage said line contacts, means at the substation for automatically causing a continuing connection of oneof said linkcircuits withsaid line contacts, `and means automatically cective to eXtend a calling signal to the operator.

16. A telephone system including a callingline, line contacts therefor at the exchange,

`operator controlled link-circuits having selective switches provided With contact meinbers adapted to .engage said line contacts,

. means at the substation. for automatically kcausing a continuing connection of one of said link-circuits with said. line contacts, nica-ns automatically effective to. extend a.

'calling signal to the operator, and a central c source of current for operating and talking 17. A. telephone' system including subscribers lines eacli'having multiple answering contacts and multiple called contacts, link circuits for connecting subscribers lines Jfor conversation, each link-circuit being c on- .nected to a. manually operated terminal for connecting with said called-contacts'and continuously traveling electrically controlled terminals for connect-ing with said answering contacts.

i8. A telephone system including subscribers lines eacli having' multipleanswering contacts and in ultipl'e'called contacts;-

, lin k-circuits for connecting subscribers lines r'for conversation,

es cli link circuit being connected to a manually operated terminal for connecting with said called contacts and continuously traveling electrically controlled terminals for connecting with said answer` ing contacts, and means at a substationA for automatically bringing the electrically controliedl terminals of a link-circuit'into a temporary continuing connection with the star tionary contactsof the line.

19. A telephonesystem including subscri'bers lines each having multiple answering contacts and-'multiple called contacts,

1s link-circuits for use in connecting subscribers linesfor conversation, each of certain of said link-circuits being connected to an operator controlled terminal for use in extending connections to said called contacts andv 15 lcertain of said link circuits being connected to traveling electrically controlled terminals adapted toassume a plurality of selective positions, for connecting with saidanswering contacts, means at a substation for automatically bringing the electrically controlled terminals of a link-circuit into a temporary continuing connection with the stationary contacts of the line, and Ameans for auto-g' matically extending a calling signal thereon. v 20. A telephone system -including a suhscribersL line, an operator controlled link circuit for use in extending connections from calling to called subscribers and a manually controlled terminal for use with Asaid link tests said line and automatically connects thereto when la calling line.

21. A telephone4 system including a subscriberis line, a link-circuit for use in ex- 35 tending connections from calling to called subscrlbers, a manually operated terminal for use with said link circuit, and means whereby said link-circuit tests said line and automatically connects thereto when a call- 40 ing line. f

22. A telephone system including a subscribers line, alink circuit and an operator controlled terminal for use, with said link circuit, a calling signal for said link-circuit,

and means whereby said link-circuit tests said line and automatically displays said signal when said line is a calling'lin'e.

23. A telephone system including a line, f

a link-circuit, a manually operatedterminal therefor, a calling signal therefor, and means whereby said link-circuit tests said line and automatically connects thereto v to display said signal when said line is a calling line.

4 24. A telephone system including a calling line, an operator controlled link-circuit for use in extending connections from calling to called subscribers and a manually controlled terminal for use with said link circuit adapted to test said line, and an automatic test device for said link-circuit sensitive to the calling condition of said line to establish a continuing connection of said link-circuit and line.

25, A telephone system including a calling I .5 line, anA operator controlled link circuit for circuit, and means whereby said link-circuit" extending connections fromv calling to called subscribers and an operator controlled terminal for use with said link circuit, means for causing said circuit to test said line, and a calling signal for said link-circuit operative on said test responsive to the calling condition of said line.

26. Attelephone system including a calling line, a link-circuit for use in extending connections from calling tov called subscribers ,75

called subscribers adapted tortest Said lines, 35

a mailially controlled terminal 'ihr said link circuit for directly connecting to said called subscribers lines, mechanisms at the substations of said lines adapted to change their Velectrical conditions `when calls are initiated 9o thereover, and means included in said linkcircuit sensitive to the changed electrical condition of any line to establish an operazive connection between said'circuit and said 2S.v A telephone system including aplarality of lines, a link-circuit yprovided with a rotary switch for testing said lines, a calling signalincluded in said link-circuit, mechanism at the` substations of said lines adapted to change their electrical conditions when calls arev initiated thereover, and means in-` eluded in said link-circuit sensitive to the changed electrical condition of any line to operate said signal.

29. A telephone system including a calling f line, a link-circuit for use in extending connections from calling to called subscribers, a manually operated terminal for use with said-link circuit, a testing device included in A11o said link-circuit' for automatically testin w said line, and mechanism controlled by sai testing device operated responsive to the calling, condition of said line to establish an operative connection between said circuit V115 Y and said line.

30. A telephone system including a calling line, a link-circuit, an operator controlled terminal for use with said link circuit, a calling signal for said link-circuit, a test- 12e ing device included in said circuit for automatically testing said line7 and mechanism responsive to said testing device and the calling condition of said line to automatically operate said signal.

3i. In a telephone system, subscribers lines', a link-circuit for use in extending connections from calling to called subscribersl having a manually operated terminal, mechanism to cause said circuit-.to success- `13o tive substations, a link circuit for extendively test said lines, and apparatus operated responsive to the 'testingofha calling line to connect said linkv circuitand" said calling line.

32: In a telephone system, lsubscribers lines, a link circuit having a manually operated terminal, a calling signal individual to said link-circuit, mechanism to cause said circuit to succV isively test said lines, and apparatus responsive tothe testing of a cal-lingV line4 to operate said signal.V a

33. In a telephone system, subscribers lines, an operator Fcontrolled link circuit for Ause in extending connections from calling to called subscribers am` a manually controlled terminal therefor, an active member for useA with said link circuit adapted for progressive travel to test said lines, and apparatus responsive to the testing of a calling line to establish telephonie connection be- .tWeen said link circuit and said calling line.

34.1n a telephone system, subscribers lines, mechanisms at the respective substations to change the electrical conditions of lines when calls are initiated at the respeclink circuit having a manually operated terminal for use in extending connections to called lines, a testing conductor for use with said circuit, motor mechanism for effecting progressive movement of said conductor to successively connect with the test contacts of said lines, and apparatus responsive to the calling condition of a line effective when the test contact of said line is connected with said conductor, to-tele-A phonically unite said link circuit and said ine.

36. A telephone system including subscribers lines, test contacts for said lines, a link-circuit including a call signal individual thereto, an operator controlled terinitial therefor for use in extending connections to called lines, an electrically operated terminal for use With said link circuit and adapted to connect with calling lines, a Y

testing conductor associated with said electrically operated terminal, motor mechanism for effecting progressive travel of said conductor to connect with the test contacts of said lines, and apparatus responsive to the calling condition of a line, effective when a test contact of said line is connected with 4said conductor, to operate said call signal.

371 A telephone system including subscribers7 lines, terminals therefor at the exchange,

`terminal for use with said link circuit, a

traveling switch individual to said link ci-rcuit adapted to engage terminals of successive lines, and means for arresting said .switch when engaging terminals of desired lines.

38. A telephone system including a subscribers line, a terminal therefor at the exchange, means at the substation for impressing an abnormal electrical condition upon said terminal, a link circuit for' use in extending connections from calling to 'called subscribers, an operator controlled terminal therefor, an electrically operated contact for use with said link-circuit adapted to connect withsaid line terminal independently of the normalfor abnormal condition thereof, and mechanism individual to said link-circuit sensitive to the abnormal condition of said line terminal to continue connectionl'of said terminal and contact.

39. A telephone system including a subscribers line, a link-circuit for use in extending connections from calling to called subscribers at .the exchange, an operator controlled terminal therefor, automatic mechanism actuated independently of the line to connect said link-circuit with said line, and mechanism for said circuit sensitive to the calling condition of said line to cause a continuing 'connection of said linkcircuit and said line.

40. A telephone system including a calling and a called subscribers line, a 'linkcircuit at the-exchange having an operator controlled terminal for use in extending connections to said called line, an'automatic switch actuated independently of the calling line to connect therewith, means atV theY calling substation adapted to effect an abnormal condition of theline and mechanism for said switch adapted, responsive to the abnormal condition of the calling line, to cause a continuing connection of said link- -circuit and said line.

41. A telephone system including a subscribers line, a link-circuit for use in extending connections from calling to called subscribers anda manually controlled terminal therefor, contacts associated with said line at the exchange, means to create an abnormal electrical condition ofisaid contacts, and electromagnetic means for use with said link-circuit, operated in response to said abnormalcon dition to operatively connect said line and circuit.

42. A telephone system including subscribers lines, contacts for said lines at the exchange, means at the substations to create abnormal electrical condition of the contacts of the respective lines, link-circuits foruse in extending connections from calling to called subscribers provided with operator .controlled terminals, and continuously travcling automatic means associated with said link circuits operated inresponse to said abnormal conditions `to connect link-circuits and lines.

43. A telephone system including a' subscribers line, passive contactslv individual to said line adapted to`be placed in an abnormal electrical condition under substation control, a link-circuit and a manually consaidlink-circuit oradvancing said contact scribers line,

trolled terminal therefor, and automatic means operating responsive to said labnormal electrical condition .to connect said linkcircuit to said line.

44. A telephone system Vincluding a subscribers line, a linlecircuitat the exchange provided with a contactvmaker capable of assuming a plurality of selective positions, a coperating manually operated terminal, advancing motor mechanism `individual to maker to connect said circuit and terminal vin circuit with saidl line, and apparatus individual to said line e. atV the exchange adapted under substation" control to automatically govern said motor mechanism.

A 45. A telephone system including a sub-V Vscribers line, a link-circuit for 4use in eir-A tending connections from calling to called subscribers, a manually operated terminal at the exchange;- motor mechanism individual to said link-circuit to connect it and said terminal in circuit With said line, an electromagnet for` controlling said motor, and a conductor individual to said line at the ex- I change for controlling said system including a sub' with said individual conductor, an electro-` magnet belonging to said circuit for con trollingsaid motor and means at the sub'- station for producingy an abnormal electrical i condition of said conductor to control said magnet. l

47. A telephone system including a suba link-circuit vfor use in extending connections from calling to called subscribersandan operator controlled terminal therefor at the exchange, automaticw mechanism operating independently of' said line to produce an exclusive operative relaand appa-` tion between said circuit and line,

ratus included insaid mechanism sensitive 48,.:A- .telephone system i sively,

' terminals, p connections from ycalling to called subscribe#` ers adapted for connection to said term'imils,l

scribers lines, a link-circuit at they exchange --provided with an operator controlled terminal for' use in, extending connections to called lines, motor mechanism for establishing' independently of vsaid lines, and succesexclusive operative relations-between 'said circuit and the different lines, and means at the substation for controlling said motor mechanism.

49. A telephone system including ay subscribers line and a link-'circuit at the exchange provided Witha manually operated terminal, mechanism including passive contacts individual to said line, mechanism '1ndividual to said link-circuit having a traveling contact maker capable of assuming a plurality of selective positions for coperation With'said passive contacts, and means said line mechawhereby the operation of nism causes a subsequent operation of the to passive contacts. n

50. A telephone system including subscribers lines, a link-circuit anda manually operated terminal for use in extending conmechanism for connecting said link-circuit consecutively with each line and apparatus responsive to the calling condition'fof aline to cause a continuing. connection. i x

51. A telephone system. including subscribers lines, a linkcircuit and a manually operated terminal for use in extending connections from calling to called subscribers, a selective switch forsaid link-circuit adapted to place said linkcircuit inoperative rel'ation With each line consecutively and means sensitive to the calling condition of aline to connect said circuit with said line. 52. A telephone'system including sub! scribers lines, terminals change, means at the latter mechanism to connect said linl-circuit l ,90 nections from calling tocalled subscribers,

therefor'at the eX- substations adapted to ei'ectabnormal electrical conditions .of said link-circuits for use in extending file traveling switches individual to said circuits" and automatic test means for said switches responsive tothe normal and abnormal conf-.f

ditions of gaged by said switch.

from calling to Lcalled subscribersl at the exline terminals successivelyenf change, a traveling switch'individual therey to, andltestmeans for said switch whereby it 'avoidsv terminals of'lines in one electrical condition and `rests in engagement with ters'elective "switch, exchange, a .manually 12`5 lminals of linesv in thegother electrical condi'-y Y to a calling condition' of said line7` effective. t when said relation exists to cause continuing 'connection of said circuit and saidline e e including sub-j; y

lQ11. t ,v.,v.f Y f 54.A A telephonev system including a calli ing line, a contactpertaining1 thereto, a

controlled switch, a link for use in extending connections from calling to called subscribers between said switches, a source of power for eiecting a progressive movement of said selective switch 'andineans for automatically rendering said source inoperative when said selective switch engages said contact of said calling line. A

55. A telephone system including a calling line, a contact pertaining thereto, a

selective' switch at the exchange, an operator controlled switch, a link intermediate of said switches, a signal for said link, a source ci power for eliecting a progressive movement of said selective switch, means tor automatically rendering said source inoperative when said selective switch engages said Contact of said calling line, and mechanism-for simultaneously displaying said signal.

56. In a signaling system, the combination with a plurality of subscribers stations, of operator controlled circuits provided with manually controlled terminals for use in connecting stations, the number of said circuits being less than the number of said subscr'ibers stations, and selective means corresponding in nuinberto that of the said cir cuits for connecting any of said stations with any of said circuits.

57. A telephone system including-a calling line, n contact pertaining thereto, a

called line, a selective switch at the eX` change., an operator controlled switch for use in extending connections to said called line, a 'link intermediate of said switches, a signal for said link, asource of power for effecting a progressive movement of said selective switch, and means for automatically rendering said source inoperative When said selective switch engages said contact of said calling line.

58. A telephone system including a calling line, a contact pertaining thereto, linkciicuit for use' in extending connections from calling to called subscribers at the exchange, a manually controlled switch for use Witlisaid link circuit, an electrically controlled switch for said link-circuit, means for .causing an independent' progressive movementthereof to connect with said contact, and an automatic test device for said electrically controlled switch sensitive to the calling condition otrs-aid line to continue connection of said link-circuit and line.

59. A telephone system includingfa a calling line, a contact pertaining thereto, linl circuit at the exchange, an operator controlled switch -.tor use With said link circuit,

an electrically controlled switch for said' liiilr-ciicnit, means for causing an independent progressive movement thereof to con neet with said contact, an automatic test device for said electrically controlled switch sensitive to the calling condition of said ,scares line to continue connection of mid link-circuit and line, a signal tor said circuit, and means for displaying` the saine When said connection is continued.

60. In a signaling system, the combination With a plurality 'of subscribers stations, ot operator controlled circuits oruse in connecting said stations, the number of said operator controlled circuits being less than the number of said subscribers stations, selective means corresponding in number to that of the said operator controlled circuits for connecting any of said stations Witlany of said operator controlled circuits, signaling circuits and meansv controlled through the signaling circuits for governing the said selective means.

6l. ln a signaling system, the combination with a plurality orn subscribers stations, of operator controlled circuits to which said stations are adapted to be connected, manually controlled terminals forsaid operatorcontrolled circuits for use in completing connections, the number of said circuits being less than the number of the said subscribers stations, selective means corresponding in number to that o'f the said circuits for connecting any of said stations with any of said circuits, driven means for actuating said selective means and means for automatically arresting each of the .said selective means in connecting position.

62. A telephone system including a call.-

ing line, a contact pertaining thereto, a linlrcircuit. at the exchange, an operator coin trolled switch for use With said link circuit,

an electrically controlled switch :for said link-circuit, means Afor causing an independent progressive movement thereof to connect With said contact, a signal for said circuit, and means for displaying the saine When said connection is established.

63. A telephone exchange system comprising telephone lines, a linlrcircuit normally disconnected from said lines having an-operator controlled terminal, a signal individual to said link-circuit, and an electricall controlled switch having an independen progressive movement for interchangeably associating said signal with different lines When callingl lines. v

64. A telephone exchange system compris- .ing telephone lines, a .link-circuit normally disconnected from said lines, a signal individual to said 'link-circuit, and means including an electrically controlled switch having an independent progressive movement, for interchangeably associating said signal with diderent lines when calling lines, and an operator controlled switch for said link-circuit for connecting with said lines when called lines.`

65. d telephone system comprisingftelephone lines, a signal at the exchange, an

ini-e automatic switch individualV to said signal, means whereby said switch consecutively tests said lines tol associate said signal with indiv1dual to said signal, driving means for causing said switch to consecutively engage said contacts, and mechanism for rendering said driving means ineffective when a contact of a calling line is engaged, and a link circuit 'for' extending the circuit of a calling toward a called line and having apparatus controllable over a connected line for' controlling said signal.

67. A telephone system comprising telephone lines, test contacts for' said lines, a

signal at the exchange, an automatic switchindividual to said signal, driving means for 'causing said switch to consecutively engage said contacts, circuit connections and a source of current for operating said driving means, mechanism for interrupting said circuit connections and thereby rendering said driving means ineiective when a contact of a calling line is engaged, and means for thereon -displaying said signal.

68. A telephone system including telephone lines, a signal common to said lines, a traveling selector switch individual to said signal and having a contact maker capable of assuming a plurality of selective positions, means responsive to the altered condition of a calling line for causing said switch to seize said line and display said signal While in association with the calling line to indicate a call and a link circuit for extending the circuit of a calling toward a called line and having apparatus controllable over a connected line for controlling said signal,

69. A telephone system including telephone lines, a call signal common thereto, a

traveling contact maker capable of assuming a plurality of selective positions individual to said signal and adapted to'interchangc- .ably associate said signal with diiierent ones of said lines to indicate calls thereover, and a link circuit for extending the circuit of a calling toward a called line and having apparatus controllable over a connected line for controlling said signal.

7 O.' A telephone, system including telephone lines, a call signal common thereto, a traveling contact maker capable of assuming a pluralityof sel ective positions individual to said signal for temporarily rendering said signal individual to a calling line, and a link circuit for extending the circuit'of a calling toward a called line, and haring apparatus controllable over a connected line for convselective means corresponding in number to trolling said signal. Y

71. A. telephone system including telephone lines, a calling telephone line, a call signal common to all said-lines, a traveling selector-,switch individual to said signal, mechanism therefor sensitive to the altered condition of said callingline to individualize said signal` to said line displaying it to indicate'thecall, and a link circuit for extending the circuit of a calling toward a called line and having. apparatus controllable over a connected line for controlling said signal. 4

72. In a signaling system, the combination with a plurality of subscribers stations, of cord circuits, for connecting stations, the number of said cord circuits being less than the number of said subscribers stations, and

that of the said cord circuits for connecting any of said stations with any of said cord circuits.

73. In a signaling system, the combination with a-plurality of subscribers stations, of signals at the central-station, said signals being of a less number than that of the subscribers stations, and selective means corresponding in' number to that of the said signals for connecting an one of said subsciiibers stations with any one of said signa s.

74. In a si aling system, the combination with a plura ity of subscribers stations,'of cord-circuits for connecting said stations, the number .of said cord-circuits being vless than the4 number of said subscribers7 stations, selective means corresponding in number to that of the said cord-circuits for connecting any of said stations with any of said cord-circuits, signaling circuits and means controlled through the signaling circuits'for governing the said selective means.

7 5. In a si ailing system, the combination with a plura ity of subscribers stations, of signals at the central station, said signals being of a less number than that of the subscribers stations, selective4 means corresponding in number to that of thesgid signals for connecting any one of saidsubscribers stations with any one 4o i said-sig@ n als, signaling circuits and means controlled through the signaling circuits for governing the said selective means.

'76. In a signaling system, the combination vgith a subscribers station, having passive terminals associated therewith, of a link circuit at the central station having a manually controlled connecting terminal and an automatic connecting terminal for connecting subscribers stations, a source of electricity connected to the said link circuit and adapted to furnish transmitter cuirents to connected stations, and means adapted to` be energized bysaid source of electricity for controlling said automatic terminal for connecting to the passive terminals of said substatio v 77. Ina signaling system, the combination with a subscribers station, of .a link circuit at the central station for use 1n confor said link circuit for completing a connection.

7,8. A telephone exchange' rsystem *Whose* telephone lines have connecting jacks and have cord-circuits provided with connecting 'plugs for insertion Within said jacks, selec'- tive switching mechanism in circuit relation With the lines for uniting calling telephone lines with idlecord-circuits and including traveling answering terminals of the cordcircuits and multipled telephone line termi nal contacts engaged by said answering terl'minals, and 'calling subscribers supervisory' signaling apparatusconnected with the cord-V circuits, substantially as described.

79. A telephone exchange system Whose telephone lines have connecting jacks and have cord-circuits provided with connecting plugs, selective switching mechanism in circuit relation Witli the lines for uniting calle ing telephone lines Witlridle cord-circuits and including traveling answering terminals of the cord-circuits and multipled telephone line terminal contacts engaged by said an! sWering terminals, and relay mechanism connected With each cord-circuit and governing the selective switching mechanism to release the'saine, substantially as described.

80. In a signaling system, the combination with a plurality of subscribers stations, of cord-circuits to which said stations are adapted .o be connected, the number of said adapted "o be connected, the number of saidA cord-circuits being less than the number of the said subscribers stations, selective means corresponding in number to that oi the said cord-circuits for connecting any o1" said stations with anyof said cord-circuits, continuously driven means for actuating said selective means and means for automatically :ir--

resting each of the said selective means in connecting position.

82. In a signaling system, the combination With a subscribersstation, of a cord-circuit at the central station for connecting subscribers stations, a source of electricity conity connected to the said link :circuit and` adapted to furnish transmitter currents to connected stations, means including a rotary switch individual V'to said link circuit for connectin said subscribers station with said link circuit, driven means for actuating said connecting m'eansy and means adapted to be energized by said source of electricity for arresting the movement of said connecting means. -A

84. In a signaling system, the combination i Awith any of said cord circuits, drivenineans for actuating said selective means and means for automatically arresting each of the said selective means in connecting position.

85. In a signaling system, the combination with a subscribers station, of a link circuit attlie central station provided with a manually controlledterminal for use in connecting subscribers stations, a source of electricity connected to the said link circuit and adapted to furnish transmitter currents -to connected stations, means individual to said link circuit for connecting said subscribers' station Withsaid link circuit, driven means for actuating said connecting means and means adapted to be energized by said source of electricity for arresting the movement of said connecting means.

86. A telephone system including a. line, a link-circuit, an operator controlled terminal therefor, a signal, means whereby said linkcircuit tests said line and automatically con nects thereto, ard ineans Jfor controlling said signal over sain in...

87. A- telephone system` comprising telephone lines, a signal at the exchange, a link circuitfor use in extending connection from calling to called lines, an automatic switch associated with said signal, means whereby said switch consecutively tests said lines-to associate said signal and said link circuit with a calling one of said lines, and test contacts for said lines. v

88. A telephone system including telephone lines, a signal common to said lines, a

y 'Y link circuit for use in extending connection' l from calling to calledy lines, an automatic traveling switch associated with said signal and said link circuit, means responsive to the condition of encountered ones of said lines `for`determining the association of said sig- Vnal and a link circuit therewith.

89. A telephone system includingr telephone lines, a signal common thereto, and a Vrotatably advancing switch associated with said signal and adapted to interchangeably associate said signal with different ones ofA said lines, said signal being thereafter under the control of an associated line.

90. A telephone system including tele-` phone lines, a plurality of signals common thereto, and means including a rotatably advancing switch individual to certain of said f signals for temporarily rendering any one of said signals individual to one of said lines.

9l. A telephone system including telephone lines, manually operated link-circuits and automatic, rotatably advancing switches individual to certain. of said link-circuits for connecting with and extending said lines.- i

92. A telephone system -including telephone lines, link circuits, an operators telephone set, and automatic switches provided with contact makerscapable of assuming a plurality of selective positions individual to ce1-tain of said link circuits for associating anidle link circuit and said operators tele- `link circuits, automatic switches provided phone set with a calling'line. v

1 controlled connecting terminals and automatic advancing switchesf'ffor use with said link circuits for connecting with vsaid lines, an operators telephone set, means controlled by 'saidoperator controlled terminals for connecting `said telephone set with any one of said link circuitsand relay controlled means for disconnecting lsaid set.'

.94. A telephone system 'including' a call'- ng line, a plurality of operator controlled with contact makers capable ofassuming a plurality of selective positions individualto said link circuits, anr operators telephone set, circuit connections :extending :from saidlink circuits to said set,'and means actuated reslponsive to a'call over said line whereby one l of said automatic switches connects its associated link circuit and extending circuit con-` nections-with said calling line.

95. A telephone systemv including telephone lines, link circuits 'having plug terminals and automatic advancing switches connected` with said link circuits for connecting With and extending said lines, an operators telephone set, -plug seat switches Vassociated with plug terminals of said vlink circuits circuits, 'an operators telephone set, means'` actuated responsive to a call oversaidcalling line whereby one y,of said automatic switches connects its linkk circuit with said callin line, means for connecting said operator s telephone with said connected link circuit, line terminals adapted to be connected with said link circuit for extending the circuit thereof, and means actuated responsive to the connecting of said link rcircuit with said terminals to disconnect Vsaid operators telephone from said link circuit. y

97. A telephone system comprising tele- A phone lines, an operators telephone common thereto, means including a traveling contact maker capable of assuming a plurality of selective positions for temporarily rendering said telephone individual to one of said lines,

and a link circuit individual to said contact maker having talking strands connectedwith said operators telephone, forextending the circuits of said'lines.

98. In a telephone system, the combina-v tion with a calling andcalled telephone line, of f manual terminals and automatic terminals for each of said lines, a link circuit havfor `com'lecting said` operators telephoneset with ing" automatic advancingterminals andan operator controlled Iterminal, means actuated 93. A telephone system including tele-.

responsive to a call from said calling line to cause said advancing terminals to .connect said link circuit with said calling' line, 'A

whereby lthe circuit of the calling line may be extended by connectingthe operator controlled terminal of said link circuit to the manual terminal of said called line.

99. lA telephone call distributing system tem, lthe combination with a plurality of.

telephone lines eachextending to a connection terminal on a switchboard, of an auto- Y Vmatic finder switch having stationary contacts'to which said lines are respectively connected, a connecting cord circuit-connected with movable terminals of said switch, and a terminal for said connecting cord circult adapted to be moved manually to completel connection with the connection termi-. y nal of any of said lines.

' circuit provided with a terminal adapted tem, the combination with a plurality of.-

to be moved manuallyto complete connection with one of said lines, a finder switch having stationary and movable contact terminals, said connecting cord circuit.being connected withsaid movable terminals, and said telephone lines being connected with different ones of said stationary terminals, and means for moving said switch to extend the circuit of any predetermined telephone line to said connectingv cord circuit.

102. In a telephone call distributing systelephone lines each extending to a connection terminal on a central oiiice switchboard, of a finder switch having stationary and movable contacts, each of said telephone lines having an extension to certain o1 said stationary contacts, a connecting circuit terminating at one end on vthe mdvable contacts of said finder switch, and at the other end on a plug adapted to be moved manually to make Connection with the connection terminal of any of said lines, andmeans for moving the movable contact terminals of the finder switch to bring them into contact with the stationary terminals of a particular line, and thus extend said line to said connecting circuit.

103. In a telephone call distributing system, the combination with a plurality of sor lines provided withl appropriate' terminals at which connection may be made therewith, ot' aV connecting cord circuit for interconnecting said lines, said cord circuit being provided at one end with a manually operated device for making connection with certain of the terminals of-said lines, and an automatic switch having traveling members upon'which the other end of said cord circuit terminates, said switch members being adapted to complete connection with another o said lines at an appropriate terminal thereof.

104. In a telephone call distributing system, the combination with a plurality of telephone` lines each extending from a substation to connection terminals at a central otlice, of a connecting circuit, a device connected with one end of said circuit adapted to be moved manually to complete connection with the connection terminals of said lines, and a inder switch having a traveling member capable of assuming a plurality of Lessines selective positions associated with the other end of the circuit and havingdconnection with the aforesaid telephone lines, said nder switch member being *adaptedV to be actuated -automatically to extend to said connecting circuit any one of said telephone lines which may be calling.

'105. ln a telephone call distributing system, the combination with a plurality of telephone lines,` each being provided with means for calling and extending from a substation to a connection terminal' on a central otlice switchboard, of a plug terminated connecting cord circuit adapted to complete connection with any of said lines at the switchboard connection terminal thereof,

"and an electrically controlled finderswitch having movable contact terminals associated with said connecting `circuit and stationary contact terminals connected with the aforesaid telephone lines, said switch being responsive to said calling means and being adapted to be actuated automatically to eX- tend the connection of a calling line to said connecting circuit.

106. In a telephone call distributing sysvtem, the combination with a plurality of telephone lines, eachextending from a substation to a connection terminal on a central4 ofiice switchboard, of a connecting cord circuit at the central oiiice provided with means adapted to be moved manually to complete connection between said circuit and any of said lines at the connection terminal thereof, a inder switch having movable terminals connected with said connecting circuit, and stationary terminals connected with said telephone lines,means associated with each telephone line adapted to cha-nge f thefelectrical condition of the associated stationary switch terminal in the use of the line, mechanism for causing said movable switch terminals to traverse the stationary terminals, and means responsive to the changed' electrical condition of the calling line adapted to arrest the movement of said movable terminals and cause them to complete connection with-,the stationary termi-v nals of said calling line.

107. ln a telephone call distributing system, the combination with a plurality of telephone lines each extending from a substation to a connection terminal on a central oliice switchboard, of a connecting circuit provided with means adapted to be moved manually 'to complete connection between said connecting circuit and any of said telephone lines at the connection terminal thereof, inderswitch having movable terminals connected with said connecting circuit and' stationary contact terminals connected with the aforesaid telephone lines, mechanism for 'causing said movable terminals to traverse said stationair 1 terminals,

.over any means made operative in initiating a call of said lines adapted to alter the condition of one of said' stationary switchv terminals associated with said line, and mechanism for arresting the movement of said movable terminals responsive altered condition o-tliestationary terminal .of the calling line,

108. In a telephone call distributing system,

l, telephone lines each extending to a connec-A to be moved manually to complete con,4

extending -rality of tion terminalrat a central oilice, of a plu-V inder switches to which said lines `are multipled, a plurality of connecting circuits each provided with means adapted nection with any of said lirios at the connection terminal thereof, one of' said connecting circuits .being associated with cachot said nderswitches and means for simultaneously moving said finder switches tocause one of them to complete connection between its associatedl connecting circuit and any of said lines. v

109. ln a telephone call distributing system, the combination with a telephone line from a substation to a central oflice, of a plurality of traveling automatic distributing switches to which said 'line is multipled, a connecting cord circuit for each of said switches connected with the traveling members thereof, to which said line is adapted to be extended, and a terniinalgfor each of said cord circuits adapted toV be the combination with a plurality .of-

to the before a different operators position,

'nals of a called line,

' 112.1n a semi-automatic telephone exchange system, the combination with a group of lines, agroup of finder switches to which said lines are multipled, each of said iinder switches being provided with la rotary contact maker for testing vthe dierent multiple stationary terminals of said line, banks of multiple called terminals of said lines, a group of connecting circuits each terminating at 'one end in an individual one of said nders and at the other end in a manual connection switch, each of said switches being locate an means actuated upon the connection of .one of said finders with a calling line for establishing an abnormal condition of said line at the multiple called terminals thereof.

113. In a telephone exchange system, the combination with telephone lines terminating in a central station, of va group ci connecting circuits at said central station less in number than the number of said lines, switching apparatus intermediate ofV said lines and connecting circuitsl controlled by any one of said lines when taken for use, for connecting such line to an idle one oi said connecting circuits, means for uniting a connecting circuit taken for use with the termiand means operated upon the completion of vsuch connection for temporarily rendering inoperative the con- .trol Vofsaid switching apparatus by the moved manually to complete connection between the aforesaidline and other lines.

llllflhey combination with a telephone lineeiitending from a substation to a con-.

nection terminal at a central oliice, of a distributing switch having' stationary and `movable contact terminals, said line termi- -natmg upon certain ci said stationary terminals, means tor causing the movable contact terminals to make contact with the stationary terminals upon which said line'terminates, and a connecting cord circuit'associated with said movable contact terminal and adapted to coperate with the connection terminals of other lines.

111. Thecombination Witha plurality of telephone lines each extending toa connection terminal at a central oiiice, of a plul rality of connecting cord circuits adapted to complete Aconnection with any of said lines ot the connection terminal' thereof, distributing switches each provided with stationary and movable contacts, the movable `contacts of each switch being connectedv with one of said cord circuits, and the stationary contacts being connected with Said lines, and means adapted to actuate one or the other of said switches to'establish connection'be- 4tween anyoi said lines and. one of said connecting cords. A

called line.v y

114. In an electric system, the combination of a plurality oli' lines, operator controlledlink circuits provided with manually controlled terminals for direct connection Y with said lilies, the number vof said link circuits being less than the number of said lines, and selecting means corresponding in number to that of said link circuits for connecting any of said lines with any ofsaid link circuits.

115. In a telephone system, the combination with telephone lines, link circuits for use in interconnecting said lines, an operators telephone set, meansactuated in respouse to a call over a calling one of said lines to connect said line and one of said link circuits, means for connecting said operators telephone set with said connected link circuit,I line terminals adapted to be connected with said link circuit for extending the circuit thereof, and means actuated in response to the connection of said link circuit withsaid terminals to disconnect said operators telephone from said link circuit with said terminals to disconnect said operoperators telephone from said .link circuit.

116. A telephone system comprising telephone lines, test contacts for said lines, an

operator controlled link circuit, an autoimatic switcliindividual to said link circuit,

erating said driving means, mechanism for interrupting said circuit connections and' thereby rendering said driving means in-A effective when a contact of a calling line is engaged, and a manually controlled'. terminal :tor said link circuit for connecting'to a f called one of said lines. Y A 117. In a telephone system, the combination with telephone lines terminating inA passivev contacts at a central station, of a group of connectin circuits at said central station less in num er l,than the number of said lines, switching-apparatiis including rotary selectors equal'in number to the number of connecting'circuits controlled by any one of said lines when taken for .use for connecting such line to an idle one of said connecting circuits, means for uniting. the connecting circuit taken for use with the terminals of a called line, and means operative upon the completion of such connection for temporarily rendering inoperative the control of said switching apparatus by the called line.

118. In a telephone system, the combination with callingl and called telephone lines terminating in passive contacts at a central station, of a group of'co'nnecting circuits at said central station less in number than the number of said lines for extending calls from said lines, switching apparatus including automatic selectors provided with active contacts and equal in number to the number of connecting circuits, said selectors being controlled over f'calling o-nes of said lines when taken for use in calling for connecting idle ones of said connecting circuits to such calling lines, means for uniting a connecting circuit taken for use with the terminals of the called line, and means operative upon the A, completion of such a connection for temporarily rendering inoperative the control of said switching apparatus by the called line.

119. A telephone system including subscribers telephone lines terminating in passive contacts ata central oilice, subscriber controlled means for changing the electrical condition of said passive contacts, a group of link circuits at the central oice less in line lindi'ng switches adapted to wipe over said passive contactsmeans for moying the contacts ct aline iinding switchinto engagement vwith the passive contacts'o-a j calling line that has had the electrical' condition of its passivecontacts changed, and means individual to the line finding switch operative responsive to the engagement of its said active contacts with the passive contacts of the calling line to prevent further movement of said line finding switch there- 'by connecting the link circuitA associated with the line finding switch with the calling subscribers line, means Afor uniting the link 'circuit takenrfor' use with a called one of said-ilines,` and means operative upon the completion ot such connection for tempofrarily rendering inoperative the control of said switching apparatus by the calling line.

' 120. A telephone system including a call. ingsubscribers line and a called subscribers line provided with passive contacts at a--cen- .tral station, means responsive to the removal of `the subscribers receiver at' the calling substation for changing the 'electrical condition of the passive contacts associated with j said calling subscribers line, a group of link circuits at the-'central station, switching apparatus including line finders equal in num- `electrical condition changed means is operated to prevent further movement 'of the active contacts of said iinder switch thereby maintaining the link circuit associated with said line finder in connection with saidy calling subscribers line, means for then eX- tending the connection from said link circuit to said called subscribers line, and means operative upon the completion of said connection to temporarily render inoperative the control of said switching 'apparatus by the called subscriber. i

121. A telephone systemincluding subscribers telephone lines terininatingin pas:

sive contacts at a central oiiice, subscriber controlled means for changing the electrical condition of said passive contacts, a group of link circuits at Ithe central oiice less in number than the number of said lines, switching apparatus including line finding switches equal in number to the number of link circuits, active contacts Afor said line finding switches, means for moving the active contacts of Aan idle one of said lieiindf ing switches into engagement with the passivecontacts of a calling line, electromagnetic 4means responsiveto the engagement of the active contacts of said linefinding switch with the passive contacts of the calling subscribers line'for preventing furthen movement of the line indingswitch, wli'ereby said calling line` remains temporarily vin connection with the link circuit associated.

with said line finding switch, means for uniting the link circuit taken for use with a called one of said lines, and means operative upon the completion of such a connection for temporarily rendering inoperative the control of said switching apparatus by the called line.

In Witness whereof, I hereunto subscribe my neme this twenty-second day of August,

1t is hereby certified that in Letters Patent No. 1,229,165, granted June 5, 1917, upon the application of Harold D. Stroud, of Chicago, Illinois, for an improvement in Telephone-Exchange Systems," errors appear in the printed specication requiring correction as follows: Page 15, line 55, claim 111,"for the word of read at; same page, claim 115, strike outI lines 12S-124; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office. signed @d sailed-this 16th any of April, A. D., 191s.

[mn] F. W. H. CLAY,

Acting Commissioner of Patents. 

